A lot of the trafficking happens across the international border with Pakistan with smugglers using plastic pipes to push heroin packets across the electrified fence or even flinging wrapped packets across the frontier.

The seizure of narcotis worth Rs 100 crore (USD16 million) by the Punjab Police on Friday and the recovery of nearly 50 kg of heroin, a high-end drug worth Rs 250 crore in the international market, in just one week by the Border Security Force (BSF) have put security agencies on a new alert.

Senior officers in the Punjab Police and the BSF said that the drugs trade was thriving in Punjab, which shares a 553-km-long international border with Pakistan.

In 2012, the BSF had recovered nearly 290 kg of heroin along the Pakistan border.

In the first four months of this year, the BSF had recovered nearly 145 kg heroin - half of last year's total seizure. In 2008, the BSF seized over 100 kg of heroin, in 2009 about 120 kg, in 2010 about 115 kg and in 2011 only around 68 kg.

"The seizures are greater because of the element of surprise in patrolling introduced by the BSF. We are trying to make our patrolling unpredictable for the smugglers," BSF Deputy Inspector General MF Farooqui said.

The seizures are being made not only in the border belt. Punjab Police and other agencies have also seized drugs this year worth hundreds of crores of rupees.

Against a heroin seizure of just over 100 kg in 2011, Punjab Police recovered nearly 280 kg heroin in 2012. In less than 10 months of this year, the seizure is nearly 279 kg, worth Rs 1,395 crore.

Earlier this year, the Punjab Police recovered over 28 kg of heroin after busting an international drug cartel operating out of Punjab. A Canadian and a Briton, both of Indian origin, were among over 20 people arrested in the case.

In February, customs officials burnt 445 kg of heroin seized in recent years. The heroin was worth Rs 2,225 crore. In 2012, customs officials seized over 135 kg of heroin being smuggled through cement bags being imported from Pakistan through the India-Pakistan goods train in just four months (July-October).

The seizure was valued at over Rs 675 crore in the international market. A whopping 105 kg of heroin worth Rs 525 crore was seized from cement bags in one consignment alone. This led to the cement trade between the two countries being suspended for some time.

The international border in Punjab is barbed-wire fenced and is under the vigil of nearly 135 BSF battalions day and night. The drug network operates along the Afghanistan-Pakistan-India route.

BSF officials say that smugglers from Pakistan use plastic pipes to push heroin packets across the electrified fence or just throw the wrapped packets across, which their Indian counterparts later pick up. The connivance of Pakistani border guards, Pakistan Rangers, with the smugglers cannot be ruled out.